“5G” is the next generation of cellular mobile communications, succeeding 4G. The 3rd Generation Partnership Project (3GPP) Technical Specification (TS) 23.501 defines a Unified Data Repository (UDR) that stores, consolidates, and manages user/subscriber data. The UDR supports the following functionality: (1) storage and retrieval of subscription data by a Unified Data Management (UDM) or Policy Control Function (PCF); and (2) storage and retrieval of data for exposure and application data.
The Home Location Register (HLR) and Subscriber Profile Repository (SPR) were the 4G Long-Term Evolution (LTE) predecessors of the UDR. Unlike the HLR and SPR, which collectively included multiple copies of a subscriber database, the UDR is centralized and is located in the same Public Land Mobile Network (PLAIN) as the Network Function (NF) service consumption. 5G also offers a network slicing capability which could be served across multiple networks owned and hosted by edge network providers, cloud service providers, and mobile network operators.